Volume-18 ~ Issue-12 ~ December 2025

Abstract: This study assessed the water quality of three springs in the city of Brazzaville (Congo). Water samples were taken from springs in district 8, Madibou. The water samples were analysed for the following physico-chemical parameters: temperature, hydrogen potential (pH), alkalimetric titre (TA), complete alkalimetric titre (TAC), hydrotimetric titre (THT), suspended solids (SS), salts of strong acids (SAF), salts of strong bases (SBF), conductivity, turbidity, colour, potassium permanganate oxidability, Ryznar index (IR), Larson index (IL), general mineralisation......

Keywords: Water, Spring, Analysis, Physico-chemistry, microbiology, Brazzaville

[1] Atteia O. Chimie Et Pollutions Des Eaux Souterraines. Editions Technique & Documentation, Paris, 2015, 448 P.
[2] Ben Abbou M., El Haji M., Zemzami M. Et Fadil F., Détermination De La Qualité Des Eaux Des Nappes De La Province De Taza (Maroc), Larhyss Journal, N°16, 2013, 77 – 90.
[3] Blum A., Chery L. Et Legrand H., L’eau Souterraine Est-Elle Toujours Potable A L’état Naturel ?, Géosciences N°5, 2007, 58 – 67.
[4] Bouchahm N., Hecini L. Et Kherifi W., Adoucissement Des Eaux Souterraines De La Région Orientale Du Sahara Septentrional Algérien : Cas De La Région De Biskra, Revue Des Sciences De L’eau, 29(1), 2016, 37 – 48.
[5] Cardot C. Et Gilles A., Analyse Des Eaux : Réglementation, Analyses Volumétriques Et Spectrophotométriques, Statistiques, Ellipses Edition Marketing S.A, Paris, 2013, 296 P..

Abstract: The toxic dye methyl red pose harmful effects on human and aquatic ecology. The focus of this work is to use different adsorbents prepared from Wood apple (Limonia acidissima) fruit shell for removing methyl red from aqueous solutions. The prepared adsorbents LAS1; chemically activated adsorbents LAS2 and LAS3; were tested for their adsorption potentials with respect to the dye. The batch adsorption experiments were carried out by using 100 mg L-1 dye solution with adsorbent dose of 0.030 g with a contact time of 90 min at 300 rpm. The adsorbents prepared by chemical activation showed significant enhancement of dye removal efficiency compared to the raw material, indicating the effectiveness of chemical activation in improving adsorption performance..

Keywords: Adsorption, Methyl red, Limonia acidissima fruit shell, Adsorption potential

[1] Roy R., Choudhury A., Synthesis Of A Novel Gellan–Pullulan Nanogel And Its Application In Adsorption Of Cationic Dye From Aqueous Medium, Carbohydrate Polymers, (2020) 227:115291.
[2] Meghwal K., Kumawat S., Ameta C., Jangid N., Effect Of Dyes On Water Chemistry, Soil Quality, And Biological Properties Of Water, In Book: Impact Of Textile Dyes On Public Health And The Environment, (2020); 1:90–114. 10.4018/978-1-7998-0311-9.Ch005.
[3] Dutta S., Gupta B., Srivastava S. K., Gupta A. K., Recent Advances On The Removal Of Dyes From Wastewater Using Various Adsorbents: A Critical Review, Mater. Adv., (2021); 2(14):4497–4531.
[4] Naseem T., Durrani T., The Role Of Some Important Metal Oxide Nanoparticles For Wastewater And Antibacterial Applications: A Review, Environ. Chem. Ecotoxicol., (2021); 3:59–75.
[5] Yadav S., Yadav A,, Bagotia N., Sharma A. K., Kumar S., Adsorptive Potential Of Modified Plant-Based Adsorbents For Sequestration Of Dyes And Heavy Metals From Wastewater – A Review, J. Water Process Eng., (2021); 42:102148.

Abstract: Aim: This study aims to develop and validate a stability-indicating comprehensive, reliable, cost-effective, rapid, robust reverse-phase liquid chromatographic (RP-HPLC) method to quantify impurities related to Rivaroxaban in drug substances and pharmaceutical formulations dosages. Material and Method: The method efficiently elutes all impurities with good resolution using a C18 with 3 μm particle size column. Simple mobile phase gradient program is used for separation of Rivaroxaban and its impurities at....

Keywords:Stability-indicating, Rivaroxaban, tablets, RP-HPLC, related substances, impurities

[1]. Xarelto: Summary Of Product Characteristics". Bayer Schering Pharma AG. 2008.
[2]. Bayer Pharma A. Xarelto® Summary Of Product Characteristics. 2015
[3]. AG BP. Xarelto® (Rivaroxaban) Summary Of Product Characteristics. 2013. 2012. .
[4]. Chandra Bala S, Vankayapati Hima Bind, Mittapati Rupa D, Anaparthi S, Development And Validation Of UV Spectroscopic Method For Determination Of Rivaroxaban, Der Pharma Chemica, 5(4), 2013, 1-5.
[5]. Suraj Sahoo, Suman Kumar M, Assay Comparison Of Rivaroxaban By New HPLC Method With An Existing Method In Tablet Dosage Form, Pharmaceutical And Biological Evaluations, 4 (3), 2017, 180-182.

Abstract: Tyramine (4-[2-aminoethyl]phenol) belongs to the trace amines, a family of endogenously synthesized compounds present in the body at nanomolar concentrations. The objective of this work is to determine the acidity and basicity constants of tyramine in the ground and excited states, with the aim of evaluating its behavior in different environments. First, the acidity constant (Ka) in the ground state was determined by varying the percentage of acidic and basic....

KeywordsTyramine, Absorption, Acidity constants of the ground (pKa) and excited (pKa*) states, Förster cycle

[1]. Naila, A., Flint, S., Fletcher, G., Bremer, P. & Meerdink, G. (2010). Control Of Biogenic Amines In Food Existing And Emerging Approaches. Journal Of Food Science, 5, R139–R150.
[2]. Linares, D. M., Del Rio, B., Ladero, V., Redruello, B., Martin, M. C., Fernandez, M., & Alvarez, M. A. (2013). The Putrescine Biosynthesis Pathway In Lactococcus Lactis Is Transcriptionally Regulated By Carbon Catabolic Repression, Mediated By Ccpa. International Journal Of Food Microbiology, 165(1), 43–50.
[3]. Alvarez, M., & Moreno-Arribas, V. (2014). The Problem Of Bio Genic Amines In Fermented Foods And The Use Of Potential Biogenic Amine-Degrading Microorganisms As A Solution. Trends In Food Science And Technology, 39, 146–155.
[4]. EFSA Panel On Biological Hazards (2011). Scientific Opinion On Risk Based Control Of Biogenic Amine Formation In Fermented Foods. EFSA Journal, 9, 2393.
[5]. FAO (2014). Assessment And Management Of Seafood Safety And Quality: Current Practices And Emerging Issues. FAO Fisheries And Aquaculture Technical Paper, P. 574

Abstract: Aim: This study aims to develop and validate a stability-indicating comprehensive, reliable, cost-effective, rapid, robust reverse-phase liquid chromatographic (RP-HPLC) method to quantify impurities related to Rivaroxaban in drug substances and pharmaceutical formulations dosages. Material and Method: The method efficiently elutes all impurities with good resolution using a C18 with 3 μm particle....

Keywords Stability-indicating, Rivaroxaban, tablets, RP-HPLC, related substances, impurities

[1]. Xarelto: Summary Of Product Characteristics". Bayer Schering Pharma AG. 2008.
[2]. Bayer Pharma A. Xarelto® Summary Of Product Characteristics. 2015
[3]. AG BP. Xarelto® (Rivaroxaban) Summary Of Product Characteristics. 2013. 2012. .
[4]. Chandra Bala S, Vankayapati Hima Bind, Mittapati Rupa D, Anaparthi S, Development And Validation Of UV Spectroscopic Method For Determination Of Rivaroxaban, Der Pharma Chemica, 5(4), 2013, 1-5.
[5]. Suraj Sahoo, Suman Kumar M, Assay Comparison Of Rivaroxaban By New HPLC Method With An Existing Method In Tablet Dosage Form, Pharmaceutical And Biological Evaluations, 4 (3), 2017, 180-182